Pen



FIG. 1 is a perspective view of a pen, showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a front elevational view thereof;

FIG. 7 is a rear elevational view thereof; and,

FIG. 8 is a right side elevational view thereof, with the writing tip in a retracted position. 

The ornamental design for a pen, as shown and described. 